1. Field of Application
The present invention relates to coated permanent-mould casting automatic lines used in foundry practice. More specifically, the invention is directed to manipulators intended for effecting separation of coated metal moulds.
It is known to produce high-quality castings in coated permanent moulds of, practically, any shape and from various metals, inclusive of cast-iron with flaked and globular graphite, carbon and alloy steels, etc. The castings may be made of various sizes ranging from dozens of millimeters to one and more meters and from hundreds of grams to 300 and more kilograms.
Coated permanent mould casting method is advantageously used for making crankshafts employed in the automobile and tractor engines, diesel engines, camshafts for automobile engines, frameworks for electric motors, axle-boxes for railway cars, hydraulic system control valve bodies, drive sprockets for tractors and many other suchlike parts.
The coated permanent-mould casting process invariably includes the steps of separating the mould after solidification of the metal poured thereinto, removing the solidified casting therefrom, and cleaning the air injection holes in the split parts of the mould.
There is known in the art various foundry system flask unloading apparatus'. In the foundry system of this type, the mould sand and cast material are separately removed from the cope and drag of a flask type foundry mould. The shake-out operation is effected by conventional methods, i.e. by subjecting the mould with the casting to jolting or else by squeezing out the content of the mould with the casting onto special broaching dies, whereupon the cope and drag of the mould are disengaged. In the event one of the mould parts, usually the drag, comprises a cross-bar, the shake-out operation is preceded by the operations of removing the mould cope and turning over the mould drag. Similar operating processes are described in U.S. Pat. No. 3,150,425 and in U.S. Pat. No. 3,199,157. In the apparatus of the patents referred to above, the mould cope is separated at one station while the operations of tilting and damping the cast material from the mould drag is effected at another station. The operation of tilting the mould cope is not effected since it is not specified by the operating process.
In the coated permanent-mould casting process, the mould top part and bottom part are to be separated before the casting is knocked out therefrom and the mould coating is removed from the air injection holes of the mould parts. The mould separating operation is preferably carried out concurrently with the broaching of holes in the mould top part, whereby the casting is held in the mould bottom part. In addition, the coated permanent-mould casting process requires the coated mould top part to be tilted so as to undergo the following technological operations, namely: the removal of used coating therefrom, the cooling and quality control of the cleaning operation effected in the flow-line production. Consequently, the flask handling equipment described in the patents referred to above is unfit for separating permanent moulds.